"I had been pushing hard for Grundhofer to replace Pandit, and I believe Jerry would have stepped in if Tim had asked him to," Bair wrote. "But Tim would not take decisive action to replace Bob Rubin's hand-picked choice for CEO, Vikram Pandit."

Her pursuit of Pandit's ouster came as he worked to repair Citigroup after it took a $45-billion bailout in 2008. Pandit, 55, lacked commercial-banking experience while the company's management struggled to make decisions, Bair wrote. Geithner, 51, wanted to shield the bank from Bair rather than protect taxpayers from potential losses at New York-based Citigroup, according to the book.

"Couldn't we at least bring in an experienced commercial banker to run the place, I asked," wrote Bair, 58. "Tim resisted, offering a bone instead: that Vikram could hire some more commercial bankers to work for him. I doubted that many senior commercial bankers would be willing to work for Vikram, given his weak reputation, but no one was going to buck Tim."

Pandit has succeeded in turning the company around since taking over during the financial crisis by paring assets and restoring earnings, Mark Costiglio, a Citigroup spokesman, said in a statement.

"Citi has executed a strategy based on returning to the basics of banking and building a culture of responsible finance," Costiglio said. "It is a simpler, smaller, safer and stronger institution than it was five years ago, and this record speaks for itself."